The Yan-Li School (Yan-Li xuepai顔李學派) was a philosophical school that was founded by Yan Yuan 顔元 and expanded by his disciple Li Gong 李塨 during the early Qing period 清 (1644-1911). Their most important concept was "learning by practice" (xi xing 習行), instead of the Neo-Confucian theorem of "learning by studying (or reading)". In his youth Yan Yuan had studies the traditional teachings of Neo-Confucianism, but soon became aware that their teachings were too abstract, metaphysical and "void" (xu 虛) for any "practical" (shi 實) use in daily life, and therefore contradicted the original intention of Confucius to live "virtue" by practical behaviour. He also saw problems in Zhu Xi's 朱熹 interpretation of human character and his interpretation of the relation between the Heavenly principle of nature (li 理) and the substance (qi 氣) of which objects consist. Yan Yuan contradicted the Neo-Confucian proposition that the principle existed before matter came into being. He held that both were joined to each other, and that without matter no "Heavenly" principle can exist.
His break-off with Neo-Confucianism was more profound than in the philosophy of his contemporarians Wang Fuzhi 王夫之, Huang Zongxi 黃宗羲 or Gu Yanwu 顧炎武. Li Gong was so impressed by the teachings of Yan Yuan that he said to abandon them would mean "to intentionally discard Heaven" (shi zi qiqi tian yi 是自棄棄天矣). He expanded Yan Yuan's theorem of the coherence between principle and matter and explained that the Heavenly principle was to be found in all things, and that without things there would be no principle. Li Gong traveled a lot as a kind of "visiting scholar" to propagate the teachings of Yan Yuan. The writings of the two philosophers were later assembled in the collectaneaYan-Li yishu 顏李遺書. On of Yan Yuan's disciples, Wang Yuan 王源, went to far to say that man would even be able to overwhelm nature with the help of practical doing and practical learning. Yan Yuan had more than a hundred disciples, to which also Wang Kunsheng 王昆繩, Yun Haowen 惲皋聞, Cheng Mianzhuang 程錦莊 and Zhong Ling 鍾錂 belonged.